Benchmarking CentOS7.4 & CentOS6.9, 15% downgrade??

General support questions
Post Reply
minl4
Posts: 2
Joined: 2018/01/05 02:12:38

Benchmarking CentOS7.4 & CentOS6.9, 15% downgrade??

Post by minl4 » 2018/01/05 03:02:02

We did a CentOS7.4&CentOS6.9 performance testing, UNIX benchmark(Version 5.1.3) results show that CentOS7.4 got a low score compare with CentOS6.9, almost 15% downgrade.

We are confused, because CentOS 7 runs a newer kernel, which is proven to be faster.
Does any know the reason? or do you have any opinion about the 15% downgrade?


Aattached files are the os performance test results for CentOS 6.9 and CentOS7.4.
Test System Information for CentOS7.4:
System: localhost.localdomain: GNU/Linux
OS: GNU/Linux -- 3.10.0-514.21.1.el7.x86_64 -- #1 SMP Thu May 25 17:04:51 UTC 2017
Machine: x86_64: x86_64

Test System Information for CentOS6.9:
System: localhost.localdomain: GNU/Linux
OS: GNU/Linux -- 2.6.32-573.el6.x86_64 -- #1 SMP Thu Jul 23 15:44:03 UTC 2015
Machine: x86_64: x86_64
Attachments
CT7.4 CT6.9_UnixBench_result.zip
(38.75 KiB) Downloaded 66 times

User avatar
TrevorH
Site Admin
Posts: 33202
Joined: 2009/09/24 10:40:56
Location: Brighton, UK

Re: Benchmarking CentOS7.4 & CentOS6.9, 15% downgrade??

Post by TrevorH » 2018/01/05 08:12:15

No idea but you are benchmarking old and out of date kernels on both CentOS 6 and 7 and you should update ASAP.

Latest el7 kernel is 3.10.0-693.11.6.el7

Latest el6 kernel is 2.6.32-696.18.7.el6
The future appears to be RHEL or Debian. I think I'm going Debian.
Info for USB installs on http://wiki.centos.org/HowTos/InstallFromUSBkey
CentOS 5 and 6 are deadest, do not use them.
Use the FAQ Luke

User avatar
centminmod
Posts: 44
Joined: 2014/07/12 14:28:06
Location: Brisbane, Australia
Contact:

Re: Benchmarking CentOS7.4 & CentOS6.9, 15% downgrade??

Post by centminmod » 2018/01/05 15:25:22

FYI, latest kernels enable KPTI - Kernel Page Table Isolation for Meltdown/Spectre security vulnerability fixes and the fixes have a performance penalty between 5-30% depending on work loads

see https://spectreattack.com/ and tunables to disable/enable KPTI etc https://access.redhat.com/articles/3311301

but your older versions don't have KPTI anyway

minl4
Posts: 2
Joined: 2018/01/05 02:12:38

Re: Benchmarking CentOS7.4 & CentOS6.9, 15% downgrade??

Post by minl4 » 2018/01/19 01:44:17

UnixBenchmark results show that, CentOS7.4 has a 26% downgrade on Shell Scripts testing, a 20% downgrade on System Call Overhead testing, and a 16% downgrade on Pipe Throughput testing. Does any one know why? Very appreciate your sharing.

Shell Scripts testing measures the number of times per minute a process can start and reap a set of 1 concurrent copies of a shell script.
System Call Overhead estimates the cost of entering and leaving the operating system kernel, i.e. the overhead for performing a system call.
Pipe throughtput measures the number of times (per second) a process can write 512 bytes to a pipe and read them back.

Post Reply